textproduct: Albany

WHAT HAS CHANGED

The southern Adirondacks, western Mohawk Valley and the Berkshires were upgraded to Extreme Cold Warnings tonight until late tomorrow morning for wind chills or "feels-like" temps as low as -25 to -30F.

KEY MESSAGES

1) There is an increased risk for frostbite and hypothermia for those who don't take precautions for tonight into Fri morning due to a combination of frigid temps and brisk west/northwest winds for eastern NY and western New England.

2) There is high confidence that snowfall should stay east of eastern NY and western New England with a coastal Nor'easter moving well off the East Coast, although brisk and very cold conditions are still expected.

DISCUSSION

KEY MESSAGE 1...

A gyre of frigid air remains over NY and New England this pm into tonight with another weak short-wave passing in the west to northwest flow aloft. Some west/northwest upslope snow showers and flurries continue along and near the western New England higher terrain with perhaps some light coatings to a few tenths of an inch of snow for the southern Greens and Berkshires. Elsewhere, some light lake effect/upslope snow showers/flurries will linger into tonight over the western Dacks, western Mohawk Valley and the northern Catskills. The bigger issue will be the cold with the reinforcing shot of arctic air. Strong low and mid level cold advection will occur over the region tonight into Friday. H850 temps drop to -1 to -2 STDEVs below normal according to the latest NAEFS with the actual H850 temps down to -20C to -25C over the forecast area. Lows will fall to 10 to 20 degrees below across the southern Dacks, portions of the Lake George/Glens Falls area, the southern Greens and the northern Berkshires. West to northwest winds 10-15 mph with some gusts 20-25 mph over the higher terrain will yield wind chills or "feels like" temps 10 to 35 degrees below zero.

We have wind chills in the -25F to-35F range over the southern Dacks, western Mohawk Valley and the Berkshires, so we upgraded the Cold Weather Advisories to Extreme Cold Warnings. Cold Weather Advisories for the rest of eastern NY and western New England for wind chills or "feels-like" temps -10F to -25F. With values this low, frostbite and hypothermia will be a concern for anyone outdoors for an extended period of time that doesn't take precautions. Frostbite can occur in as little as 30 minutes (as low as 10 minutes over the Adirondacks) on exposed skin.

The headlines run until 11 am Fri, and not much recovery will occur during the day with high temps only in the single digits to lower and spotty mid teens in the valleys. Portions of the Adirondack Park and the southern Greens will remain below zero with brisk winds. Another night of frigid temps will occur for Fri night into Sat morning with lows 5 to 20 degrees below zero. The winds will go light to calm with weak ridging, so it will be more of a frigid radiative cold. Additional headlines will likely be needed with continued cold weather impacts. Sunday will be more of the same and we will monitor for future headlines, as winds kick up for the coastal low passing northeast from the outer Banks of the Mid Atlantic towards southeast New England and Cape Cod.

KEY MESSAGE 2...

The coastal or oceanic deep and intense low passing tracks well south and east of Long Island and Cape Cod Sun-Sun night according to the majority of the ensembles and medium range guidance. The NBM PoPs are still in the 15-30% range Sun-Sun night for western New England/mid Hudson Valley/southern Taconics. We placed some light snow in here, but a shift eastward will likely occur with light dustings or less than a half inch with the systems outer mid/upper deformation zone. It will be cloudier to the east of the Hudson River Valley and it will become brisk with northwest to north winds 10-20 mph with some gusts 25-30 mph. Highs on Sunday will be in the teens to lower 20s...and lows fall back to 5 above to 5 below zero over most of the region. Wind chills or apparent temps will be zero to 15 below, with some colder readings over the highest terrain Sun night into Monday morning. Some cold weather impacts impacts or isolated large tree limbs could fall over the western New England higher terrain due to the oceanic Nor'easter.

AVIATION /00Z FRIDAY THROUGH TUESDAY/

Through 00Z Saturday, mainly VFR conditions are expected despite occasional clouds with Cigs of 3500-5000 FT AGL. At KPSF, upslope clouds may produce occasional MVFR Cigs overnight, with a lower chance of MVFR Cigs occurring during Friday. In addition, at KPSF, there is a low chance for snow showers/flurries overnight which could produce brief MVFR/IFR Vsbys. Overall probability for Vsby restrictions is low, and have not included mention in current TAFs.

West to northwest winds will average 5-10 KT overnight, although may remain slightly stronger along with a few gusts up to 20-25 KT at KALB and KPSF. On Friday, west to northwest winds will increase slightly to 8-15 KT by afternoon, with some gusts up to 25-30 KT possible, strongest and most persistent at KALB and KPSF.

Outlook...

Friday Night to Tuesday: No Operational Impact. NO SIG WX.

ALY WATCHES/WARNINGS/ADVISORIES

CT...Cold Weather Advisory until 11 AM EST Friday for CTZ001-013. NY...Cold Weather Advisory until 11 AM EST Friday for NYZ039>041- 043-047>054-058>061-063>066-083-084. Extreme Cold Warning until 11 AM EST Friday for NYZ032-033-038- 042-082. MA...Extreme Cold Warning until 11 AM EST Friday for MAZ001-025. VT...Cold Weather Advisory until 11 AM EST Friday for VTZ013>015.